Sheave assembly for crown blocks



June 14 1932- w. D. DAvsDsoN ET AL 362885 SHEAVE ASSEMBLY FOR CROWN BLOCKS Filed Jan. 5. 1927 III /m AYTTHNM Patented .irme 14, 1932 s'rres PATENT Frio WILLIAM D. DAVIDSON AND EDW 12N W'. GOESER, OF LOS ANGELES, CALIFORNIA, AS- SGNOR-S TO EMSCO DERRICK & EQUPMENT COMPANY, OF LOS ANGELES, CALI- FORNIA, A CORPORATION OF CALXFORNA SHEAVE ASSEMBLY FOR CROWN BLOCKS Application filed January 3, 1927. Serial No. 158,546.

' body.

Our invention relates to crown-blocks such as are employed in oil well equipment and relates particularly to a novel adjustable sheave assembly which forms a part of such crown-blocks.

In the oil producing industry the crownblock is installed at the top end of the derrick above the well. The crown-block includes a number of sheaves over which cables used at different times are passed. 1t is frequently necessary to ,adjust the positions of the sheaves and it is therefore desirable that they be readily adjustable. In the ordinary Crown-block Vthe sheaves are mounted on shafts which are rotatably supported by bearings, these bearings being in turn supported by I-beams of the crown block.

It is an object of this invention to provide a sheave assembly in which the sheave shaft is secured to the supporting beam and clamped against being rotated by means of the same structure.

The side thrust of the sheave againstA either of the shaft supporting blocks is sometimes very great. In those types of blocks which have a body and a separate cap bolted to the body, all of the thrust is taken by the block because the cap cannot be clamped against sideward movement rela-tive to the Any slight sideward movement of the cap will place all ofthe thrust-forces of the sheave on the body.

It is an important object of this invention to provide a bearing box of this character, which provides an integral and completely annular bearing face for taking the thrustforces of the sheave.

A further object of the invention, and a very important one, is to provide a shaft supporting structure of the character mentioned, having a body for supporting a shaft, means for restraining the shaft from rotation, and an integral bridge extending over said shaft at one end of said body, thus forming a completely annular bearing face at one endV of said body.

It is another object of this invention to provide a sheave assembly in which the bearing between the shea-ve andthe shaft is held arranged in i pairs.

provide a sheave assembly having no loose parts which can fallr from place.

@ther objects and advantages of the in vention will be made evident hereinafter.

Referring to the drawing in which we illustrate oui invention.

Fig. 1 is a fragmentary view showing a crown-block embodying our invention mounted at the top end of a derriclr.

Fig. 2 is a fragmentary plan view of Fig. 1.

Fig. 3 is a section taken on the line 3--3 of F ig'. l.

F ig. t is a section taken on the line 4-4 of Fig. 3. 1 Y

Fig. 5 is a section of Fig. 3. Y

Referring in detail to the drawing, the numeral v11 represents the upper end of a derrick to which av crown-block 12 embodying the features of our invention is secured. The crown-block 12 is provided with a number of parallel extending I-beams 14. The sheave assembly of our invention is shown best in Figs. 3 to 5 inclusive. Placed on the 1- taken on the line 5 5 beams 14 which comprise supporting members of the crown-block are boxes 16 which are The boxes 16 engage upper flanges 17 of the I-beams 14 and have projections 18 which extend downward adj acent to the opposite edges of the flanges 17 in order to prevent the boxes from moving sidewise on thefI-beams. The boxes 16 are, however, free to slide along the I-beams when they are not clamped in place, as will be described later. The boxes 16 have openings 20 `formed therethrough. The inner parts of the boxes 16 are provided with bridge portions 21 which form upper walls of the openings 20. The outer ends of the boxes 16 do not have bridge portions and therefore the outer endsof the openingsQO are only partly cylindrical so that the upperl portions are connected to the exterior of the boxes.

Adapted to be supported by pairs of boxes 16 is a shaft 24. The end portions of the shaft 24 which rest in the openings 2O of the boxes 16 are substantially the same diameter so that a good fit is obtained. The portions of the shaft 24 which rest in the outer parts of the boxes 16, where the upper parts are cut away, are provided with fiat faces 25. The fiat faces 25 are placed at the top as illustrated best in Figs. 3 and 4.

The boxes 16 are secured to the I-beams 14 by securing means provided in the form of bolts 27. The bolts 27 extend through vertical openings 28 formed at the outer parts of the boxes 16 on opposite sides of the shaft 24. 'I he lower ends of the bolts 27 are provided with heads 29 which are adapted to project under the flanges 17 and engage lower faces thereof. The upper ends of the bolts 27 extend through openings 36 of a clamp means provided in the form of a clamp plate 31. There is a clamp plate 31 for each box 16 and a pair of securing bolts 27 extends through each clamp plate. rIhe clamp plates 31 are adapted to engage the flat faces 25 of the shaft 24. Screwed onto the upper ends of the securing bolts 27' are nuts The nuts 33 pull the securing bolts 27 upward so that the heads 29 thereof firmly engage the lower faces of the flanges 17 and secure the boxes to the I-beams 14. rihe clamp plates 31 are forced downward into firm engagement with the flat faces 25 of the shaft 24, and the shaft 24 is thus locked from rotation. It should be noted that the same means is employed for (l) securing the boxes to the i-beams, and (2) clamping the shaft from rotation.

rIhe shaft 24 is provided with a. central hardened race portion 35. Surrounding the race portion 35 is a bearing 36. The bearing 36 in the form of the invention shown in the drawing is provided in the form of a roller bearing. Adapted to rotate on the shaft 24 is a sheave 37. rlfhe sheave 37 surrounds the race portion 35 of the shaft 24 and has a race opening 38 in which the bearing 36 is located. Side plates 39 are placed on opposite sides of the sheave 37 between the edges thereof and the inner edges of the boxes 16.

As shown best in Figs. 3 and 5, pins 41 are screwed into the shaft 24 on opposite sides of the sheave 37, the bearing 36, and the side plates 39. Heads 42 of the pins 41 are so placed that they may engage the side plates 39. rhe purpose of the pins 41 is to prevent the parts 36, 37 and 39 from moving from proper position on the shaft 24 when the boxes 16 are not in place. When the boxes 16 are placed, the heads 42 of the pins 41 rest in recesses 43 formed in the inner parts of the bridge portions 21.

In Figs. 1 and 2 we show a crown-block having a. number of sheave assemblies of our invention supported by the I-beams 14. It should be noted that the sheave assemblies are so designed that they may be adjusted into almost any desirable position. The boxes 16 extend but a short distance outward beyond the -beams 14 and they may therefore be moved very close to a box of another sheave assembly without interfering with the sheave 37 thereof. This is illustrated best in Fig. 2.

One important feature of our invention is that the boxes 16 and the shaft 24 are easily secured in place by the same means. This means comprises the bolts 27 and the clamp plates 31. It should be noted that these bolts and clamp plates are attached to the boxes 16 in such a manner that they may be loosened to permit the shea-ve assemblies to be slid along the I-beams 14 and to permit the boxes to be moved from the shaft 24 without entirely detaching them from the box. This is a desirable feature because there are no small parts detached which may be easily but unintentionally dropped to the derrick floor below. rThe shaft 24, the bearing 36, the sheave 37, and the plates 39 are retained together by means of the lock pins 41. None of the parts may fall from place when this assembly is being assembled with the two boxes 16. rEhe sheave assembly of the invention may be considered as consisting of three main parts which are assembled together, these parts being the assembly of the shaft and sheave and the assembly of the boxes and bolting means.

Another important feature of this invention is the providing of the boxes 16 with bridge portions 21. By this construction the boxes 16 are provided with completely annular bearing faces which are positioned on each side of the hub of the sheave 37. The side thrusts of the hub of the sheave against the boxes 16 are sometimes very heavy, and it is therefore desirable to provide 'solid faces to receive this thrust. The clamp plates 31 which are attached to the boxes 16 by the bolts 27 are not called upon to resist any thrusts of the sheave 37. In order to reduce wear between the hub of the sheave and the annular faces of the boxes, the side plates 39 which are in reality hardened thrust washers are placed between the adjacent faces of the boxes and the hub of the sheave.

We claim as our invention:

1. In combination in a crown-block: a shaft; a sheave rotatably mounted on said shaft; boxes embracing said shaft on opposite sides of said sheave, said boxes being supported by supporting members, and said boxes having integral bridge portions so that said boxes have annular bearing faces adjacent to said sheave; securing means for securing said boxes to said Supporting members; and clamp means for clamping said shaft from rotation.

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2. In combination in a crown-block: a shaft; a sheave rotatably mounted on said shaft; boxes embracing said shaft on opposite sides of said sheave, said boxes being supported by supporting members; and said boxes having integral bridge portions so that said boxes have annular bearing faces adjajacent to said sheave; bolts for securing said boxes to said supporting members; and clamp means for clampingvsaid shaft from rotation.

3. In combination in a crown-block: a shaft; a sheave rotatably mounted on said shaft; boxes'embracing said shaft on opposite sides of said sheave, said boxes being supported by supporting members; and said boxes having integral bridge portions so that said boxes have annular bearing faces adjacent to said sheave; bolts for securing said boxes to said supporting members; and clamp means engaged by said bolts for clamp ing said shaft from rotation.

4. A combination as defined in claim l in which said clamp means engages a flat face on said sha-ft.

5. In combination in a crown-block: a shaft; a sheave rotatably mounted on said shaft; boxes embracing said shaft on opposite sides of said sheave, said boxes being supported by supporting members, and said boxes having integral bridge portions so that said boxes have annular bearing faces adjacent to said sheave; bolts for securing said boxes to said supporting member; and clamp plates adapted to engage fiat faces of said shaft and being engaged by said bolts for clamping said shaft from rotation.

6. In combination in a crown-block; a shaft; a sheave surrounding said shaft; a bearing disposed between sai-d shaft and said sheave for journaling said sheave; boxes placed on said shaft on opposite sides of said sheave; and means for holding said sheave and bearing in proper position on said shaft when said boxesare not in place, said means being enclosed by said boxes When the combination is assembled.

7. In combination in a crown-block: a shaft; a sheave surrounding said shaft; a bearing disposed between said shaft and said sheave for journaling said sheave; boxes placed on said shaft on opposite sides of said sheave; means for holding said sheaveand bearing in properv position on said shaft When sai-d boxes are not in place, said means being enclosed by said boxes when the combination is assembled; and means for clamping said shaft from rotation.

8. In combination in a crown-block: a shaft; a sheave surrounding said shaft; a bearing disposed between said shaft and said sheave for journaling said sheave; boxes placed on said shaft on opposite sides of sai-d sheave; and pins attached to said shaft on each side of said sheave for holding said sheave and bearing in proper position on said shaft When said boxes are not in place7 said pins being enclosed by said boxes When the combination is assembled.

9. In combination in a crown-block: a shaft; a sheave surrounding said shaft; a bearing disposed between said shaft and said sheave for journaling said sheave; boxes placed on shaft on opposite sides of said sheave; pins attached to said shaft von each side of said sheave for holding said sheave and bearing inproper position on said shaft When said boxes are not injplace, said pins being enclosed by said boxes When the combination is assembled; and means for clamping said shaft from rotation.

10. In combination in a crown-block: a shaft; a sheave rotatably journaled on said shaft; kboxes on opposite sides of said sheave for supporting said shaft; and means on each sideof said sheave for holding said Y sheave in proper position on said shaft when said boxes are not in place, said boxes having recesses to receive said holding means when said box-es are in place.

l1. In combination in a crown-block: a shaft; a sheave rotatably journaled on said shaft; boxes on opposite sides of said sheave for supporting said shaft; and pins attached to said shaft on each of said sheave for holding said sheave in proper position on said shaft When said boxes are not in place, said boxes having recesses to receive said pins When said boxes are in place.

l2. In combination: a box having an opening; a bridge portion integral With said box, said bridge portion extending over a part of said opening, the other part of said opening being open; a shaft extending into said opening; clamp means engaging said shaft at the open end of said opening; and means for applying pressure to said clamp means to force it into tight yengagement With said shaft.

13. In combination: a box having an opening; a bridge portion integral with said box, said bridge portion extending over a part of said opening at one end of said box so as to provide an annular bearing face, the other part of said opening being open; a shaft extending into said opening; clamp means engaging said shaft at the open end of said opening; and means for applying pressure to said clamp means to force it into tight engagement With said shaft.

14;. A bearing box of the class described comprising: a body having a face adapted to be secured against a supporting member, an opening extending from one side of said body to the other side; and a bridge portion inte-f' gral with said bo'dy,'said bridge portion extending over said opening at one end of said body thus forming a completely annular bearin face at one end of said body.

shaft supporting box of the char-v' acter described, including: a body having a shaft receiving recess formed by an annular vvall portion adapted to surround a shaft placed in said recess and a parti-annular Wall portion integral with said annular Wall portion leaving an opening adjacent a side of said recess; a member in said opening in position to engage said shaft; and means for securing said boX to a support, said means engaging said member and causing it to clamp said shaft in said box.

16. A shaft supporting box of the character described, including: a body having a shaft receiving recess formed by an annular Wall portion adapted to surround a shaft placed in said recess and a parti-annular Wall portion integral with said annular Wall portion leaving an opening at a side of said recess; means in said opening in position to engage a shaft placed in said recess; and means for simultaneously securing said box to a support and said shaft in said box.

17. A shaft supporting box of the character described, including: a body having a shaft receiving recess formed by an annular Wall portion adapted to surround a shaft placed in said recess and a partifannular Wall portion integral with said annular Wall portion leaving an opening at a side of said recess; a member in said opening` in position to engage a shaft placed in said recess; and bolt devices for securing said box to a supporting member, said bolt devices engaging said member and causing it to clamp said shaft l placed in said box.

In testimony whereof, We have hereunto set our hands at Los Angeles, California, this 24th day of December, 1926.

WILLIAIVI D. DAVIDSON.

EDl/VIN W. GOESER. 

